Processes to convert alcohols to gasolines using ZSM-5 type catalysts are described in J. Catal. V. 115, N.1, p. 233-43 (1989) and J. Catal. V. 47, N.2, p. 249-59 (1977). Typical processing conditions include a temperature of about 725.degree. F. and a pressure of about 300 psig.
Japanese Patent No. JP 6310337 teaches the use of ZSM-5 zeolite to convert TBA to isobutylene. The dehydration is carried out at a temperature of about 250.degree.-350.degree. F. and pressures at or above 75 psig.
It has now been found that tertiary alcohols can be converted over a catalyst composition comprising a large-pore, 12-membered ring material to give high yields of C.sub.8 + olefins with very little dehydration products. Therefore, it is an object of the present invention to provide a novel process for tertiary alcohol conversion to higher octane C.sub.8 + olefins. It is a further object of the present invention to provide a process for the conversion of t-butyl alcohol to C.sub.8 + olefins. It is another object of the present invention for the conversion of isobutane to high octane gasoline components.